Congestive heart failure (CHF) is a common and lethal disease. A new diagnosis of CHF is made in 400,000 Americans each year. Those with moderate left ventricular dysfunction have a death rate of 25% over 2 1/2 years, with 50% thought to be due to arrhythmias. The central hypothesis of this study is that amiodarone or an implantable cardioverter-defibrillator (ICD) will improve survival compared to placebo in patients with NYHA Class II and Class III CHF and reduced left ventricular ejection fraction, less than or equal to 35%. The study will be a prospective, clinical trial with 2,500 patients randomly allocated in equal proportions to three different treatment arms over 2 1/2 years. The first arm of the study will consist of conventional heart failure therapy and placebo. The second arm of the study will combine conventional therapy with amiodarone. The third arm of the study will employ conventional therapy with a pectoral ICD. Treatment arms will be compared using an intention-to-treat analysis. We have one primary specific aim: 1. To compare all cause mortality-based on a minimum of 2 1/2 years of follow-up in the three arms of the study. We have five secondary specific aims: 1. To determine the incidence of cardiac mortality and arrhythmic mortality, 2. To determine the incidence of VT/VF and profound bradyarrhythmias (rates less than or equal to 30 bpm) in CHF patients in the ICD arm via the ICD memory log, 3. To compare morbidity in each of the three arms of the study, 4. To compare health-related quality of life in the three arms of the study, 5. To compare cost of care for each treatment group and calculate incremental cost-effectiveness ratios for the two intervention arms. The study will be performed at 95 North American Institutions. The Clinical Coordinating Center is the University of Washington in Seattle while the Data Coordinating Center and the Economics and Quality of Life Coordinating centers are at Duke University. The ICD Memory Log Core Laboratory is a subunit of the Clinical Coordinating Center focusing on secondary specific aim #2.